ICELAND GULL

Larus glaucoides

Status: Uncommon regular spring and fall migrant Lake McConaughy, Keith Co and Sutherland Reservoir, Lincoln Co, rare elsewhere. Uncommon winter visitor  Lake McConaughy and Sutherland Reservoir, rare casual elsewhere.

DocumentationDescription: 15 Jan 1907, Dorchester, Saline Co (Swenk 1907, Bray et al 1986).

Despite the existence of a cline from west to east (dark to light) in overall coloration within forms assigned as “groups” to L. glaucoides by Chesser et al (2017), we consider it virtually impossible to assign most or all Nebraska records, especially of paler individuals, to their “groups”, presumably subspecies groups, and cite only the earliest Nebraska specimen that is clearly a representative of the cline.

Taxonomy:  Formerly considered separate species in North America, Iceland Gull and Thayer’s Gull, the two taxa were lumped into a single species with three subspecies, glaucoides, kumlieni, and thayeri, in 2017 (Chesser et al 2017).  The decision to merge the two former taxa was based on non-assortative mating between them on Baffin and Southhampton Islands and questions about the validity of earlier research.

The status of the former L.g. kumlieni is poorly known but the taxon was retained as a separate “group” by Chesser et al (2017). Although Snell et al (2020) showed that there is a complete unbroken cline in overall coloration from west to east, including even the easternmost and palest population of L. g. glaucoides in Greenland, Howell and Mactavish (2003) showed that kumlieni is clearly separable from thayeri, but reserved a conclusion on the relationship of kumlieni to glaucoides until variation in the latter has been investigated. See Comments.

There are 10 documented spring reports for Nebraska, eight for fall, and 13 for winter of birds previously identified as Iceland (Kumlien’s) Gull as opposed to Thayer’s Gull, before the two were merged (Chesser et al 2017); these 31 records are described in Gubanyi (1996a, 1996b) and Brogie (1998, 1999, 2004, 2005, 2012, 2014, 2015, 2016). There were three additional reports in spring 2020 of “kumlieni” types and one was in Lancaster Co 19-28 Dec 2020.

SpringFeb 13, 17, 17 <<<>>> Mar 30, 30, Apr 1 (away from Lake McConaughy and Sutherland Reservoir)

Earlier dates are 9 Feb 2015 Harlan Co, and 9-16 Feb 2013 Lancaster Co.

Later dates are 12 Apr 2018 Lancaster Co, and 21 Apr 2020 Garden Co.

  • High counts: 14 (Thayer’s) at Lake McConaughy 18 Mar 2020, 8 there 1 Mar 2015, 7 there 22 Feb 2004, 7 there 27 Mar 2011, and 6 at Carter Lake, Douglas Co 25 Mar 2014.

Fall: Nov 10, 12, 14 <<<>>> Dec 6, 8, 8 (away from Lake McConaughy and Sutherland Reservoir)

Earlier dates are of a first-year bird well-studied at Branched Oak Lake, Lancaster Co 1 Oct 2011, 3 Oct 2011 Lancaster Co, an adult photographed at Lake Ogallala, Keith Co 4 Oct 1997, a first-year bird at Gavin’s Point Dam, Cedar Co 7 Oct-4 Dec 2018, 23 Oct 2020 Knox Co, 29 Oct-7 Nov 2019 Cedar Co, 30 Oct 2020 Douglas Co, 5 Nov 2019 Hall Co, and 7 Nov 2019 Cedar Co.

Later dates are 13 Dec 2017 Harlan Co, 29 Nov-18 Dec 2010 Lincoln Co, 19-21 Dec 2020 Lancaster Co, and 19-28 Dec 2020 Lancaster Co. For Jan dates, see Winter.

Adults often arrive in fall before immatures.

Winter:  Recent reports at Lake McConaughy indicate that this species winters regularly, sometimes in numbers; most reports are of former Thayer’s Gull.  Overwintering is unknown away from Lake McConaughy and Sutherland Reservoir, Lincoln Co; at the latter location, six were present 14 Jan 1998, five on 31 Dec 1998, and five on 29 Jan 2000.

The few mid-winter records away from Lake McConaughy and Sutherland Reservoir are 10 Jan 2012 Lancaster Co, 22 Jan 2000 four Harlan Co Reservoir, Harlan Co 22 Jan 2000 Johnson Lake, Gosper/Dawson Cos, 22-25 Jan 2012 2-3 juveniles Harlan Co Reservoir, 13 Dec-30 Jan 2015 Harlan Co Reservoir, and 6-18 Feb 2013 Lancaster Co. Overwintering may occur on occason at Harlan Co Reservoir.

In the period 6 Dec 1997-18 Apr 1998 at Lake McConaughy, age-class totals were 11 first basic, one third basic, and eight adults, for a total of 20 birds.

  • High counts15 at Lake McConaughy 4 Mar 1998, 14 (Thayer’s) there 9 Dec 2020, 11 there 14 Jan 2001, 10 there 6 Feb 1999, and 9 at Sutherland Reservoir 1-3 Jan 2011.

CommentsAs with other large gull species, reports of former Thayer’s Gulls in Nebraska have dramatically increased since the 1990s.  The increase can be attributed both to an increase in numbers present due to the number of ecologically mature reservoirs and the increasing amount of identification literature available. Former Thayer’s Gull was first reported in Nebraska in 1981 in Douglas-Sarpy Co 17-21 Mar without details (Cortelyou 1991), but not documented until 17-19 Dec 1992, the seventh report of the species, when Rosche described one at Sutherland Reservoir (Morris 1993).  Most Nebraska records of Iceland Gull (sensu Chesser et al 2017) are of former Thayer’s Gull (thayeri), but there have been several reports of puzzling paler birds. There are no documented occurrences of the “glaucoides group” (sensu Chesser et al 2017) of Iceland Gull for Nebraska, although some photographed juveniles have been very pale. Most, however, are probably referable to kumlieni (sensu Howell and Mactavish 2003). Photographs of several of these birds are available at the Nebraska Ornithologists’ Union website.

There has arisen in recent years an additional problem of separation of paler Iceland Gull from the small western North American race of Glaucous Gull, L. hyperboreus barrovianus (see that species). This has been problematic on the West Coast for some time, and has manifested itself at least once in Nebraska, where the identity of a bird at Branched Oak Lake 1-7 Dec 1996 was unresolved (Silcock and Jorgensen 1997). A very small white-winged gull at Lake McConaughy 9 Feb 2021 (Mlodinow, eBird.org) was initially thought to be a glaucoides Iceland Gull but bulky structure and field marks suggested Glaucous Gull. The identification was confirmed by Louis Bevier and Bruce Mactavish; subspecies barrovianus, occurring mostly in the Bering Sea area and the Pacific Coast, was considered unlikely on geographic grounds; there are no confirmed Great Plains records of barrovianus.

Abbreviations

NOURC: Nebraska Ornithologists’ Union Records Committee

Literature Cited

Bray, T.E., B.K. Padelford, and W.R. Silcock. 1986. The birds of Nebraska: A critically evaluated list. Published by the authors, Bellevue, Nebraska, USA.

Brogie, M.A. 1998. 1997 (Ninth) Report of the NOU Records Committee. NBR 66: 147-159.

Brogie, M.A. 1999. 1998 (Tenth) Report of the NOU Records Committee. NBR 67: 141-152.

Brogie, M.A. 2004. 2003 (15th) Report of the NOU Records Committee. NBR 72: 59-65.

Brogie, M.A. 2005. 2004 (16th) Report of the NOU Records Committee. NBR 73: 78-84.

Brogie, M.A. 2012. 2011 (23rd) Report of the NOU Records Committee. NBR 80: 112-122.

Brogie, M.A. 2014. 2013 (25th) Report of the NOU Records Committee. NBR 82: 131-146.

Brogie, M.A. 2015. 2014 (26th) Report of the NOU Records Committee. NBR 83: 125-138.

Brogie, M.A. 2016. 2015 (27th) Report of the NOU Records Committee. NBR 84: 138-150.

Chesser, R.T., K.J. Burns, C. Cicero, J.L. Dunn, A.W. Kratter, I.J. Lovette, P.C. Rasmussen, J. V. Remsen, Jr., J.D. Rising, D.F. Stotz, and K. Winker. 2017. Fifty-eighth supplement to the American Ornithological Society’s Check-list of North American Birds. Auk 134: 751-773.

Cortelyou, R.G. 1981. 1981 (Fifty-sixth) Spring Migration and Occurrence Report. NBR 49: 38-55.

Gubanyi, J.G. 1996. 1992, 1993 (Fifth) Report of the NOU Records Committee. NBR 64: 30-35.

Gubanyi, J.G. 1996. 1995 (Seventh) Report of the NOU Records Committee. NBR 64: 132-138.

Howell, S.N.G., and B. Mactavish. 2003. Identification and variation of winter adult Kumlien’s Gulls. Alula 1: 2-15. http://www.gull-research.org/papers/papers4/Identification%20and%20Variation%20of%20Winter%20Adult%20Kumlien’s%20Gulls.pdf

Morris, R. 1993. Fall 1992 Occurrence Report (July 1 – December 31). NBR 61: 31-87.

Silcock, W.R., and J.G. Jorgensen. 1997. Winter Field Report, December 1996-February 1997. NBR 65: 17-27.

Snell, R.R., P. Pyle, and M.A. Patten. 2020. Iceland Gull (Larus glaucoides), version 1.0. In Birds of the World (P. G. Rodewald and B. K. Keeney, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.y00478.01.

Swenk, M.H. 1907. Two interesting Nebraska records. Auk 24: 223.

Recommended Citation

Silcock, W.R., and J.G. Jorgensen. 2021. Iceland Gull (Larus glaucoides). In Birds of Nebraska — Online. www.BirdsofNebraska.org


Birds of Nebraska – Online

Updated 13 Apr 2021